Improve speed of stdlib functions by replacing `re` uses
We can often find the module re in the standard library modules but it can be replaced (if it is possible). I don't suggest removing it everywhere, there are places where its use is appropriate, but there are also places where it is an unnecessary solution and leads to unpleasant consequences (they can be found below)
Cons of regular expressions and reasons to replace regular expressions with functions and methods:
- We spend time to compile re pattern (one time, but anyway we spend it)
- In most cases simple string methods are faster (according to my benchmarks about 2x)
- We can remove
import rewhich will affect import time - Additionally: I think for those who don't know regular expressions, the code is more difficult to read and therefore difficult to maintain.
Important
For those who want to work on the issue, please:
- Read https://devguide.python.org/getting-started/pull-request-lifecycle/ before anything else.
- Select one function to improve. It's easier to review and possibly backport.
- Always report benchmarks using
pyperf,hyperfine, andtunatogether with-X importtimeto compare import times and execution time. - Open a pull request with the following title:
gh-130167: Improve speed of `module.function` by replacing `re`
Linked PRs
- gh-130167: Improve speed of
difflib.IS_LINE_JUNKby replacingre#130170 - gh-130167: Improve speed of
inspect.formatannotationby replacingre#130242 - gh-130167: Improve speed of
ftplib.parse150by replacingre#130243 - gh-130167: Optimise
textwrap.dedent()#131919 - gh-130167: Minor
textwrap.dedent()optimization #131925 - gh-130167: Add a What's New entry for changes to
textwrap.{de,in}dent#131924 - gh-130167: Improve speed of
_pydecimal._all_zerosand_pydecimal._exact_halfby replacingre#132065 - gh-130167: Improve the error case for
textwrap.dedent#132666 - [3.14] gh-130167: Add a What's New entry for changes to
textwrap.{de,in}dent(GH-131924) #143292